Heavy earthmoving vehicles in which failure in the power train or other major component occurs must frequently be towed to repair facilities for servicing. At such times, it is desirable to have a quick and simple means for disconnecting the final drives of such vehicles from the traction units thereof in order to avoid the forceable turning of the gear train with consequent damage to such gear train and to the final drive motor due to operation thereof in a lubricant starved condition during towing.
Furthermore, a normally spring force applied hydraulically released brake unit is commonly integrated with the final drive system as a safety feature. In such brake-equipped vehicles, failure of the power plant or related auxiliary equipment, such as a hydraulic fluid system, frequently prevents the hydraulic release of the brake system so as to require special mechanical provisions for release of the brake before towing can commence. Thus, there is a need for a disconnect system which selectively decouples both the final drive and brake mechanism of the vehicle to allow unimpeded towing for repairs.
Another particularly vexing problem has been to design a universal final drive casing which in association with a disconnect system can be utilized in connection with the final drive unit on either side of the vehicle without modification. Such provisions would result in tremendous savings in time and manufacturing processes as well as in storage and shipment costs.
Some partial solutions to the noted problems are offered by the constructions disclosed in U.S. patent applications Ser. Nos. 211,368, 244,413, and 311,823, cited above. However, none of the referenced systems teach an interchangeable final drive casing or the extremely simple means associated therewith for disconnecting the final drive of the vehicle from the traction means thereof which are presented herein.